Generally, the present invention relates to a garage door operator system for use on a closure member moveable relative to a fixed member. More particularly, the present invention relates to an operator-controlled motor for controlling the operation of a closure member, such as a gate or door, between a closed position and an open position. More specifically, the present invention relates to an operator-controlled motor for a door or gate operator, wherein additional power is allowed by the motor to overcome hindrances in door movement.
For convenience purposes, it is well known to provide garage doors which utilize a motor to provide opening and closing movements of the door. Motors may also be coupled with other types of movable barriers such as gates, windows retractable overhangs and the like. An operator is employed to control the motor and related functions with respect to the door. The operator receives command signals for the purpose of opening and closing the door from a wireless remote, from a wired wall station or other similar device. It is also known to provide safety devices that are connected to the operator for the purpose of detecting an obstruction so that the operator may then take corrective action with the motor to avoid entrapment of the obstruction.
Safety devices come in many forms for use with a garage door operator. One of the more widely used devices is a photo-electric eye which projects a light beam across the door""s travel path. If the light beam is interrupted during closure of the door, the operator stops and/or stops and reverses the travel of the door. This is sometimes referred to as a non-contacting or an external safety device. Contact type safety devices such as an edge-sensitive pressure switch, which is attached to the bottom edge of the door and runs the complete width of the door, may also be used. Other contact safety devices directly monitor the operating characteristics of the driving motor to determine whether an obstruction is present. Typically, shaft speed of the motor is monitored by projecting an infrared light through an interrupter wheel. Alternatively, Hall effect switches or tachometers can be used to monitor shaft speed. Or, the motor current could be monitored such that when an excessive amount of current is drawn by the motorxe2x80x94which indicates that the motor is working harder than normalxe2x80x94it is presumed that an obstruction has been encountered. It is also known to monitor door speed with a sliding potentiometer, wherein a rate of change is equated to the speed of the door and wherein unexpected slowing of the door triggers corrective action by the operator. Regardless of how the safety devices work, their purpose is to ensure that individuals, especially children, are not entrapped by a closing door. Opening forces of the door are also monitored to preclude damage to the operating system for instances where an object or individual is caught upon a door panel as the door moves upwardly.
How safety devices are used with a door operator system have evolved from the days of no uniform standard to the currently applied government regulations as embodied in Underwriters Laboratories Standard 325. The basic standard requires the use of a fail-safe external safety device, such as a photo-electric eye, that is connected to the operator. Use of the external safety device allows either a wired wall station or a wireless remote control device to send a signal to the operator to close the door when the user exerts a momentary push and release force upon an actuation button. To open the door, one may also use a push and release of the appropriate wall station or remote control switch. If, for whatever reason, the safety device is disabled, a constant pressure force applied to the wall station switch or to a remote control switch in the line of sight of the operator will allow the door to close. It is presumed that the user is watching the path of the door for objects which may be entrapped in the path of the door. The safety standard will not allow the constant application of pressure on a remote device out of the line of sight to close the door. However, momentary pressure on either the remote device switch or the wall station switch will allow the door to open even if the safety system is disabled.
A newer generation of operating systems have been found to provide improved sensitivity to extraneous forces applied to a door during its movement. One such device is disclosed in U.S. Pat. No. 6,161,438, which is assigned to the present assignee of this invention and which is incorporated herein by reference. Briefly, this patent discloses use of a potentiometer coupled to the door for determining a plurality of positional locations between the open and closed positions. A processor contained in the operator correlates the position of the door with an applied force for use in comparison to a predetermined threshold. If, during movement of the door, the applied force is outside the limits of the predetermined threshold, corrective action can be taken. With this increased sensitivity, the safety standard allows use of the above operator system without an external safety system on anti-pinch doors. Anti-pinch doors use sectional panels that preclude the entry of objects, such as fingers, between the door panels during opening and closing cycles. As before, actuation and release of the switch opens and closes the door. Constant pressure on the switch has no affect on the operator. If an obstruction is encountered and a force is exerted which exceeds the threshold, corrective action is taken. However, if a door is a pinch-type door, then the external safety device must be used with the operator. In this embodiment, actuation and release of the switch opens and closes the door. If the external safety device detects an object in the presence of the door path, then corrective action is taken. And if the force required by the motor to move the door exceeds the threshold limit, then the operator also takes corrective action.
With the foregoing in mind, it will be appreciated that controls for a motorized garage door operator regulate the motor speed to a constant velocity of the door. This constant speed can be detrimental to a garage door when the operator first begins to move the door. Accordingly, motor controls have been developed that reduce the voltage supplied to the motor during start-up to allow for a xe2x80x9csoft start,xe2x80x9d preventing damage to the door and also for a xe2x80x9csoft finish.xe2x80x9d Some manufacturers use a reduced speed start then ramp up the motor to increase the door speed to minimize door opening time and, sometimes, closing time. Both of the speed adjustments are controlled by the operator""s motor controls.
These motorized garage door operators are known to have force adjustments that can be either mechanically or electronically controlled. This allows the installer, or the consumer, a way of adjusting the force that the motor exerts on the door. The amount of force to move the door will vary with the weight of the door, but can also vary as the environment changes and as the door system becomes worn with age. Generally, the information necessary to properly set these limits is contained in the owner""s/installation manual. However, in the case of a door frozen to the floor, one must increase the force adjustment to free the door. In the event the adjustment is not reset, the door""s safety settings are not what they should be. The same also applies if the door is opened when one of the counter-balance springs are broken and the force limit is not reset after the springs are replaced. Accordingly, there is no safe and secure way to provide additional power to the motor to lift a door frozen to the ground or to accommodate for broken springs in the operator and then to return the door operator system to its preferred operation mode. These conditions or hindrances are especially problematic when ensuring that the operator complies with the aforementioned safety standard. Therefore, there is a need in the art for an operating system that complies with safety regulations and that allows for application of increased force to accommodate special situations wherein operation of the door is hindered.
It is thus an object of the present invention to provide a system and method for the application of additional force when needed for a door or gate that moves between an open and close position. The door or gate is of the type that is moveable into an out-of-proximity with a fixed surface that is to be sealed relative to the door. The door or gate is coupled to a motorized operator which controls movement of the door.
It is another object of the present invention to provide a connection between an external safety system and the operator. The external safety system may be a photo-electric eye or the like. It is yet another object of the present invention, as set forth above, to provide an operator that receives signals from the safety system to assist in the operation and control of the motor.
It is a further object of the present invention, as set forth above, to provide a mechanism such as counter-balance springs coupled to the operator to assist in moving the door in a desired direction
It is yet another object of the present invention, as set forth above, to provide a switch that generates control signals that are received by the operator. The switch may be remotely actuated, a hard-wired control button, a remote control button, an alpha-numeric keypad, or the like.
It is still another object of the present invention, as set forth above, to provide an operator to utilize a force profile to monitor the operating characteristics of the motor with respect to door position during door travel. It is still a further object of the present invention, as set forth above, to provide an operator that initiates corrective action whenever the motor applies a force outside the predetermined threshold. It is an additional object of the present invention, as set forth above, to provide an operator which is micro-processor based that contains the necessary memory, hardware, and software for storing a force threshold and software routines for measuring forces for comparison to the force threshold.
It is still yet another object of the present invention, as set forth above, to allow the user to operate the door and apply a force in excess of the predetermined threshold to overcome hindrances, such as wind, parasitic drag, freezing of the door panels, and the like. One such hindrance may be a broken counterbalance spring. Accordingly, it is a further object of the present invention to allow the operator to detect a broken spring condition based upon excessive door speed while closing and allowing the operator to reduce the motor""s speed and/or stop and reverse the motor.
It is still a further object of the present invention, as set forth above, to allow for the operator to detect the presence and operability of an external safety device. If the operator determines that a safety device is not provided, the operator uses its normal operating profiles and compares actual data thereto. If the safety device is present, the operator determines this directly and if the door is moving in an opening direction, the operator is instructed to use a normal profile for comparison purposes. However, if the door is traveling in a closing direction, the operator uses an enlarged or broader force threshold to allow for application of xe2x80x9cmore powerxe2x80x9d to the door until the door is closed. And it is another object of the present invention to allow application of power to the motor, even if a broken-spring condition is detected, but only when constant pressure is applied to the main operating device.
It is still yet another object of the present invention, as set forth above, to overcome hindrances or binding problems associated with movement of the door even if a safety device is not enabled, wherein the user has a way to override the force profile provided by the operator. Accordingly, if the operator detects a constant pressure applied to an operating switch, such as a wall station or a remote control, the operator determines which direction the door is traveling. Accordingly, if the door is traveling up an expanded upward force profile is employed or if the door is traveling down, an expanded downward force profile is used.
In general, the present invention contemplates a door operator for moving a door including a motor for moving the door between opened and closed positions, an operator for controlling the operation of the motor, and a switch for enabling the operator to control operation of the motor, wherein pushing and releasing the switch results in the operator allowing the motor to apply a normal range of torque values, and wherein pushing and holding the switch results in the operator allowing the motor to apply a broader-than-normal range of torque values. The invention also contemplates a door operator for moving a door includes a motor for moving the door between opened and closed positions, an operator for controlling the operation of the motor so that the motor applies a normal range of torque values, an external safety device coupled to the operator, and a switch for enabling the operator to control operation of the motor, wherein if the external safety device is enabled and the door is closing, the motor applies a broader-than-normal range of torque values. The invention further contemplates a method for overcoming hindrances encountered by an operator-controlled motor coupled to a garage door includes actuating and releasing a switch to initiate operation of the operator-controlled motor for the purpose of opening/closing the garage door, determining that the garage door is not completing the opening/closing cycle because of a hindrance, and re-actuating and holding the device to re-initiate operation of the operator-controlled motor to overcome the hindrance and complete the opening/closing cycle. And the the invention also contemplates a method for overcoming hindrances encountered by an operator-controlled motor coupled to a garage door includes actuating and releasing a switch to initiate operation of the operator-controlled motor for the purpose of opening/closing the garage door, ascertaining whether or not an external safety system is enabled and operational, applying a normal torque value to the motor if the external safety system is not operational, and applying a broader-than-normal torque value if the external safety system is operational.
These and other objects of the present invention, as well as the advantages thereof over existing prior art forms, which will become apparent from the description to follow, are accomplished by the improvements hereinafter described and claimed.